This project had its roots in the practical problem of how to index literature data bases while preserving the authors' terminology. Each author often utilized two or more words, with overlapping meaning, to convey intent. Several thousand such pairs of words were subjected to computer analysis to determine the network character of their relationships. Their linkages formed a 3-dimensional network. Words near the center connoted control of response to assure survival. Outward from the center, words differentiated into ever more complex meanings through 7 steps of transition. Our model building led to three assumptions: (1) Each step in complexity of meaning represents an evolutionary advance in capacity for awareness and response accompanied by changes in brain function. (2) Words representing the nodes of this network reflect preverbal capacities of mammals to be aware of moods and emotions associated with experiencing day-to-day events. (3) Such awareness represents primitive conceptualization. As a specific modeling exercise we examined the inner core of the network, the portion possible characteristic of primitive extinct mammals (see Project No. Z01 MH 00847-01). By this model, such a mammal has a potential awarness for over 5,000 experientially based moods and emotions.